Registering mechanism.



C. SUL

REGISTERING ANISM.

IIIIIIIIIIIIIIIII EB. 24

' 8. 1,135,552, Patented Apr. 13, 1915.

15 E ETHKEET 1.

C. SULFER.

REGISTERING MECHANISM.

APPLICATION mm FEB. 24. I908.

1,135,552. Patented Apr. 13, 1915.

15 SHEETSBHBET 2.

C. SULFER.

REGISTERING MECHANISM. APPLICATION FILED FEB. 24. I908.

1,135,552. Patented Apr. 13, 1915.

16 SHEETS-SHEET 3.

C. SULFER.

REGISTERING MECHANISM.

APPLICATION r1150 FEB124, 1908.

1,135,552. Patented Apr. 13, 1915.

15 SHEETS-SHEET 4.

R RQN R C. SULFER.

REGISTERING MECHANISM.

APPLICATION FILED FEB. 24, I908.

1,135.552. Patented Apr. 13, 1915.

15 SHEETS-SHEET 6.

V ESE: filf (/71 1'! 1: 5 1:

C. SULFER.

REGISTERING MECHANISM.

APPLICATION FILED 3.24. 1908.

Patentd Apr. 13, 1915.

15 SHEETS-SHEET 6.

C. SULFER.

REGISTERING MECHANISM.

APPLICATION FILED FEB. 24. mos.

Patented Apr. 13, 1915.

16 SHEETS-SHBET 7.

C. SULFER.

REGISTERING MECHANISM.

aprucmou HLED FEB.24. 190a.

Patented Apr. 13, 1915.

16 SHEETS-SHEET 8.

C. SULFER.

REGISTERING MECHANISM.

APPLICATION FILED FEB. 24, 1908.

1,135,552, Patented Apr. 13, 1915.

15 SHEETS-$31121 i- C. SULFER.

REGISTERING MECHANISM.

APPILICATION FILED FEB. 24. I908.

1,135,552, Patented Apr. 13, 1915 16 SHEETS-SHEET 10.

C. SULFER. REGISTERING MECHANISM.

APPLICATION FILED FEB. 24. 1908. 1,135,552. Patented Apr. 13, 1915. 15 SHEETS-SHEET 11.

J/ CkqfZes 4-WV/MZ4 C. SULFER.

REGISTERING MECHANISM.

APPLICATION men 5.24. 1908.

Patented Apr. 13, 1915.

15 snns'rssnnm 12.

C. SULFER.

REGISTERING MECHANISM.

APPLICATION FILED FEB. 24, 1908.

"mm x mm a a 3m 1 J; LT u p I An 3 8 mm 5 n e C; SULFER.

REGISTERING MECHANISM. APPLICATION F ILED FEB. 24, 1908.

1,135,552, Patented Apr. 13, 1915.

16 SHEETS-$3551 14.

C. SULFER.

REGISTERING ME CHANISM. APPLICATION FILED [58.24. 1908.

Patented Apr. 13,1915.

CHARLES SULFER, OF CHICAGO, ILLINOIS,

ASSIGNOR TO DIAL CASH REGISTER COMPANY, OF MILWAUKEE, WISCONSIN, A CORPORATION OF ARIZONA.

REGISTERING I IECHANISM.

Original application Specification of Letters Patent.

Patented Apr. 13, 1915.

filed December 29, 1906. Serial No. 350,057. Divided and this application filedFebruary 24, 1908. Serial No. 417,530.

To (dire/10m it may concern:

Be it known that 1. Cinemas SULFne, a citizen of the United States and a resident of the city of Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Registering Mechanism; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawings. and to the letters of reference marked thereon, which form a part of this specification. h

This invention relates to improvements in registering mechanism and has for its object a mechanism whereby a plurality of independently rotatable shafts may e: :h actuate inde 'iendent regis was of a combined registering mechanism and each of which carries from a lower to ahigher denomination. It is a further object of the invention to provide a mechanism whereby a plurality of independenly rotatable shafts each appropriated to an order of digits each actuates a cor; :sponding register. and afford connection bot\\'een said mechanisms whereby co acting and cooperating means transfer the amount registered on each lower denomination register to a. register for each higher order.

It is an important object of the invention i to aiford mechanism whereby proportional fractional rotation of a sha ft or series of independent shafts shall each register upon suitable mechanism a number indicating the extent of its rotation to afford in connection therewith mechanism for returning the shaft ter each record to its normal posi tion preparatory to another count.

lt is a further object of the invention to afford mechanism rotative in character for :ntnating as many recording mechanisms as there. are rotativc or partly relative shafts and to afford coaeting mechanism to transmit the movement of said shafts to the reg ster the part of which are lirmlv loclwl from movement except when engaged in ac-- taming it own p:-.rticnlar register or carrying from that register to one of a higher order.

'llninvention shown embodied in connection n ith the cash reg ter the sub ect of my prior application for patent filed on the position.

"fragmentary plan view 29th day of December, 1906, Serial No. 350,057, though obviously it is capable of adaptation for any type of cash registers and in many devices other than cash registers.

The invention consists in the matters hereina-fter described and more fully pointed out and defir ed in the appended claims.

In the -.lrawings:l igure 1 is a front elevation of a cash register used in connection with a device embodying my invention. Fig. 2 is a top plan view of the same with the casing removed and with parts broken away. Fig. 3 is a side elevation of the same with parts omitted. Fig. 4 is a horizontal central section taken along the dial shafts with the registering mechanism secured in Fig. 5 is a central vertical section tahen along the dial shafts. Fig. 6 is a side elevation of the registering mechanism. Fig. 7 is a section taken on line 7-7 of Fig. Fig. 8 is a section taken on line S-S of Fig. Figs. 9, 10 and 11 are details illustrating the operation of a part of the mechanism'for actuating the visible signals. Fig. 12 is an enlarged vertical section of one of the pivoted supports for the pawl bars. Fig. 13 is an enlarged detail of one of the toothed wheels or cams. Fig. It is an enlarged top plan view of one of the dial shaft gears with the lifting cam and stops thereon. Figs. 15 and 16 are details of the locking means for the dials. Fig. 17 is an enlarged section taken on line 17 -17 of Fig. (i. Fig. 18 is an enlarged section tal en on lines lS--lS of Fig. (v. Figs. 19 to 2t inclusive are enlarged sections taken on cor respondingly numbered lines on Fig. l) and illustrate znljustment operation. Fig. 25 is an additional detail of one of the locking pawl Fig. lb is a section taken on line lo--28 of Fig. Fig. 27 an enlarged of the yoke and springs for supportin he pawl bars when disphrving the visible signals. Fig. 38 is an enlarged fragmentary detail of the governor shaft and one of the gears. Fig. 29 is an enlarged fragmentary longitudinal section of the transmission sha ft and the mechanism carried thereon. Fig. :10 is a fragmentary longitudinal sectional view of the register shaft and gears. Fig. 3l is an enarged fragmentary detail of the bell cranks for elevating the visible signals. Fig. 32 is a front elevation thereof. Figs. 33 and 3% are enlarged details of the arm or lever carrying the visiblesignal. Fig. 35 is an enlarged detail in section of one of the spring pressed finger pieces set in each dial.

As shown in said drawings: the mechanism is mounted upon a base A, within a suitable removable casing and is supported within a frame consisting of end plates a and a, which are rigidly secured to the baseplate A. Journaled centrally on said end frame members and supported upon suitable bearings, is a shaft 15, which protrudes through the front frame plate a and a dial B is rigidly secured thereon having marked at equal distances apart near its periphery, the numerals and signs $1, $2, $3, 35% and $5, reading from the bottom upward. Of course any desired numb r of dollars, to and including nine dollars may be indicated thereon. As shown, a standard B is supported on the base and affords a support for the end of said shaft B. Said shaft B is journaled near its middle portion on an upright or standard I), supported on the base plate A, as shown in Fig. Rotatively mounted on said shaft concentric therewith and extending inwardly thereon, from the front end, is a tubular shaft C, having a dial C thereon, similar to the dial B, and rotative around the same and marked consecutively on approximately half its periphery to indicate dimes from 10 cents to 90 cents, inclusive, and mounted to rotate on said shaft U, is an outer tubular shaft D, having a dial D, rigidly secured thereon, and marked 1 to 9 inclusive on a semi-circle to indicate pennies. Said dial is shaped to fit around the dial C. All the dials are arranged with their faces in the same vertical plane as shown in F 1 and 4. Beneath the numeral 1 on the dial 1) and at the same distance therefrom, the numerals from each other, is marked 1X0 sale. As shown said numerals on each dial are marked upon a circular button d secured in suitable sockets in the dials and which are made of east or pressed metal, or any ma terial suitable for the purpose, and a spring d shown in Fig. 35, normally holds the other face of said button flush with the face of the dial but permits the same to be pushed inwardly to enable the finger to engage in the socket to rotate the dial.

Rigidly secured on the shafts B, C and D are camsor wheels, such as shown in Fig. 1?, and indicated as a whole by B C and D for the respective shafts, these .as shown, are provided each with a single angular tooth b*czl. The number of said cams on each shaft is the same as the number of stations on its dial, in other Words there are ten on the shaft D, nine on'the shaft C and five on the shaft B, and

these are arranged and rigidly secured so that the teeth on each set are spaced equal distances apart in approximately a semi-circum ference to correspond with the arrangement of the numerals on the dial. Said cams are spaced a slight distance apart on the shaft, by means of a relatively thin plate a of metal engaged between adjacent cams, as shown in Fig. 4, and are rigidly secured on their shafts by keys or by a projection suitably positioned with a central bore one of which 50 is shown in Fig. 13. They are also secured in place by means of nuts d 0 b threaded on the respective shafts and be tween which and the cams, on each shaft is rigidly secured a gear wheel b"0*cl*".

Rigidly secured to the front and rear frame plates a-ct by means of its downwardly bent ends 0-4;, as shown in Figs. 3, 7 and 8, is a rigid horizontal bar E, which is positioned at the left of and above the dial shafts, and a central depending bracket 0 is secured at about the middle thereof, and extending through said bracket and the end (2 of said bar, is a non-rotative shaft 6. Pivoted on said shaft 6 between the bracket 0 and the end bracket 6 are inwardly directed arms a -e, which extend to near and above said gears 01 said dial shafts, and are connected intermediate their ends by a rigid horizontal bar E on which just at the rear of the gears (P and 0 are secured inwardly directed rigid arms E These are in length equal to the projection of the arm 6 beyond the bar E and each is provided with a downwardly directed spring controlled pawl 6 at its extren'iity positioned to be engaged by a came secured on the rear side of each gear wheel, on each dial shaft, and

which acts to lift all said arms simultane 1i. ously as shown in Figs. 7, 8, 9, 10 and 11.

Also secured on said shaft 1;, and projecting forwardly over the bar E are relatively broad leaf springs c, the inner edge of which is bent downwardly at a right angle for its entire width affording a detent c". Said spring plates are held in firm bearing upon the bar E by means of springs 0 as shown in Figs. 3, 7 and 8, which-bear against the same and beneath a .top plate a Rigidly secured on said arms e and a are upwardly directed inwardly hooked arms a which engage over the plate a, at their upper ends and limit the downward movement of the arms, but permit the arms to swing upwardly against the tension of the spring.

Hinged on the base plate A opposite each set of cam wheels is a standard shown more plainly in Figs. 9 to 12 inclusire. This, as shown, comprises a projection or boss 7', rigidly secured to the base plate, and on the top of which is hinged a tubular body F, as shown in Fig. 12, in which is slidably engaged a cylindric and threaded 5 yided on the top plate (D.

stem f, held from turning therein by means of a pin f secured in said stem and extending into a longitudinal slot, in said tubular body. Said stem is adjusted as to height by means of a nut f and a jam nut f, secured on said stem and bearing on said body F, and whereby the stem is supported at an adjusted height on the upper end of said body. The upper end of said stem, as shown, is provided with a head f, in which is rigidly engaged an upwardly and inwardly curved blade or plate f having its upper edge f, directed horizontally and longitudinaliy of the machine and rounded to afford a support, and of a length to extend across the face or edge of all the cam wheels in the set opposite which it is secured. Supported at their inner ends on the upper rounded edge 7'' of said hinged supports, are transversely slidable pawl bars G, which equal in number the cams in each set and are positioned respectively directly above each of the cam wheels. Each is provided at its inner extremity with an upwardly directed projection or tooth g, adapted to engage beneath and behind the downturned lip or detent e of the leaf spring 0. As shown also each is provided near said end on its under side with a notch having downwardly and outwardly inclined sides toward the adjacent end of the bar, and the other side thereof affords a somewhat rounded shoulder g Directly above each cam wheel a downwardly extending tooth g is proeach pawl bar, adapted to be engaged only by the tooth on the corresponding cam wheel. As shown also said pawl bars between the tooth on each, and the shoulder 9 is cut away to afford an inclined face for engagementby the teeth on the cams as the same are rotated forwardly thereby lifting the ends of the pawl bars. At the opposite end said pawl bar is pivotally engaged and suppo'ted upon a lever G, the upper end of which projects above As shown also a comb g is secured beneath the top plate, and the teeth thereof extend downwardly between the said pawl bars, holding the same positioned each directly above its actuating cam. Arranged obliquely on the upper side of the top plate as shown in lfiig. 2, is a set of hell cranks H, ten in rumber corresponding with the number of camson the penny shaft 1'),

and, rods 71, connect the forwardly directed arms 'h with the upper end of the lever G, before described.

The opposite arm 7r, which' is directed transversely the machine, ispivotally engaged by a rod h, which leads rearwardly, and is adjustably connected i i-th -a downwardly directed arm h, of a ever it which is pivotally supported at the tear end of the frame, shown in Fig. 5.

"Sad: levers extend forwardly through a vertical combh, and are each provided .at their forward ends with an upwardly directed arm h, on the upper end of which is a tablet it", which may be as shown of circular or any desired or suitable form and on the front and rear faces of which there is marked or indicated the numeral, sign or other representation or' representations contained upon the button of the dial from which said pawl isactuated. There are, of course, as many of said levers as there are stations on all the three dials including the No sale station. Inas-nuch as ten of said levers are appropriated to penny dial, nine to the dime dial and five to the dollar dial,

there are ten ofsaid bell cranks on the so g on the pawl bar, sa d teeth on the cams engage and successively lift the pawl bars, against the tension of their springs 1*", shown in Figs. 7 and 8, until the couipietion of the forward movement or count of the dial. \Vhen the dial is released at the end of the forward movement. the tooth d, c or b on the cam, corresponding with the count to be represented and which has just passed and is in advance of the tooth g on the cor responding pawl bar, immediately engages said tooth g as the dial returns to its normal position. Said pawl bar is moved laterally thereby pushing the h nged support F, therewith and elevating the adjacent ends of the ren'iaining pawl bars (owing to the inclined surface of the notch in each of said pawl bars in which the top of the support rests) to a height to let the remaining teeth on said cams pass beneath without contact.

The end of the positively actuated pawl bar passes beneath the spring plate a. to be retained by the detent thus elevating its tabs let into view and supporting the same until a dial is again actuated when the cam 0 engages the pawl a. on the end of one of' the cams Or arm 6 or E. lifting the some and releasing the pawl bar and permitting the visible signal to fall.

Of course any suitable mechanism may be provided to return lhe'dials and cams to position for the next count. F or this purpose, however, gears I, are journaled on standard 2', rigidly secured on the base plate and in mesh with the gears d*-r:/,- respectively, for each set of cams, and secured to the. axle or shaft for each said gears and to said standards i are strong coiled springs i which are wound up by rotation of the respective dial shafts when actuated by their dials, and act to quickly return the dial actuated to normal when released. As shown in Fig. 8, means are provided to insure the dial always stopping at normal. For this purpose a stop i which-may be integral with the cam projection e is rigidly secured on the dial shaft gear b*0*(l and engages the top of the appropriate standard when the dial at normal. In the same manner the opposite end of said stop or any-suitable stops 2' may be provided on said gears to engage the standard i or any suitable rigid part oi the machine, to limit the downward movement of the dial when actuated to make its maximum count. As shown, both said stops and the cam projection e are formed from single plates of the proper size and shape and rigidly secured on the rear side of each gear. The return movement of the dial and the cams under the action of said springs, is also regulated to prevent pounding or injury to the machine. For this purpose a governor is provided comprising a shaft J journaled on suitable standards JJ J secured on the base plate A and gears j are rotatively secured thereon in mesh with the positively driven gears I, for each dial. As shown in Figs. 4', 7, and 28, a disk j, is rigidly secured on each gear j and bearing against the face of said d sk is a ratchet j, rigidly secured on said shaft J, and which is engaged by a spring controlled pawl 1' on said disk j, thereby rotating the governor shaft J, as the dial returns to position. On the rear end of said governor shaft J, is secured a gear 1 j, which meshes with a pinion j, secured on the same sha it with a gear j which in turn meshes with a pinion j, which drives a centrifugal. governor J of any suitable kind, and which is provided at one end with a fiction brake wheel 7' adapted to be engaged by a shoe 7' as shown in Fig. 3. Said governor is obviously driven on the return nur-xcment of the dials when any one or more of the dials are actuated and acts to retard Q the return movement of the dial to prevent shock durto violent impact of the stops 11 on the standards 2' though of course if necessary nail governor may bedriven when the dials a re rotating in either or both directions.

Accurate mechanism for positively registering each transaction and at any time showing the sum of the transactions of the day or a longer period is provided. For this purpose a registering inechanisn'i is secured in the side of the machine opposite the gov ernor upon a removable base plate M, which is bolted or secured on the base plate A and extends for nearly the length of the machine. Secured thereon are uprights or tandards m-m and m which project hereon upwardly and i'.1wardl v toward the gears b-cd* on the dial iligidly secured on said base plate M, between the standards mm' and m and shafts.

the dial shafts are standards Z-Z, and rigidly secured therein is a horizontal shaft L, as shown in Figs. a, 6 and 29'. Jonr naled thereon adjacent the standard Z, is a rotatable sleeve N, provided at its end adjacent the standard with an integral gear n, which meshes with the penny gear d, on the dial shaft D. Also integrally secured on said sleeve is a crown gear n provided with nine teeth spaced 36 apart, to indicate the significant digits on the penny dial and having one vacantspace for the No sale station on said dial. Said teeth of, as shown, comprise rounded pins, set in the face and near the periphery of the gear and projecting toward the rear, as shown in Fig. 21. At the rear end of said sleeve is provided an integral disk 11 provided on its periphery with an upwardly projecting tooth n as shown in Fig. 6, the action of which will be later described. At the rear end of said sleeve a collar n is rigidly secured on the shaft L and together with the standard Z holds said sleeve always in operative position with the gear a, thereon, in mesh with the penny gear d In the same manner a sleeve 0 is rotatively secured on said shaft L on the front side of the standard Z, and is provided at its forward end with an integral gear 0, which meshes with the dime gear 0*, on the dial shaft At the rear of gear 0 is a crown gear 0 corresponding in all respects with the crown gear 'n before described and provided as shown, with nine teeth 0 similar to those thereon. At the rear end of the sleeve is a disk 0 provided with an upwardly directed tooth 0, corresponding with the tooth n on the disk if, said sleeve is held at all times in operative position with its gear 0 meshing in the dime gear cflby means of a collar 0 and the standard Z.

At the rear side of the standard Z is secured a sleeve 1, provided with a gear 79 thereon which meshes with the dollar gear Z), on the dial shaft B and at the rear end of said sleeve is an integral crown gear p as shown in Figs. 4 and 29, provided With inwardly directed teeth 29 corresponding in number with the number of stations on the dollar dial B, or as shown five, which are spaced equal distances apart near the periphery of the gear.

Journaled in the standards mmm' and a standard or post m at the rear end of the plate M, is a horizontal shaft Q, at approximately the same level with the shaft L and which is the registering shaft for pennies. Secured on the end of the shaft Q, beyond the standard m, is a .ratchet g having its teeth directed upwardly ahd inwardly, and which are engaged by a spring pressed pawl (7 secured on the standard m, whereby the shaft Q is held from rotation except that outwardly and dq nwa-rdly or r to I rotating the crown gear 0 thereby,

side "of the standard in other words in the direction of rotation of the penny dial shaft- D, in ringing up the transaction. At the rear side of said standard m, and rigidly secured on said shaft Q, is a wheel N, as shown in Figs. 21 and 30 having pivoted thereon ten radially and outwardly directed projecting teeth n which extend into position to be engaged by the teeth 11, of the crown gear n. As shown more plainly in Fig. 21', said teeth n are each provided with an integral inwardly directed tail n, adapted to engage on a pin n positioned adjacent to the pivot to hold said teeth from swinging in their pivot when engaged by the teeth n on the crown gear during the rotation of the dial to make its count, thereby rotating the shaft Q but which swing downwardly on their pivot permitting the teeth a to pass the same, as the dial and crown gear return to normal position. As shown, a spring 11, is secured on. each tooth and acts to hold the same normally directed outwardly, in position to be engaged with the teeth of the crown gear. At the rear end of said shaft Q, is a penny indicating wheel which is rigidly secured thereon. This, as shown, in Fig. 3, is provided on its periphery with the ten digits arranged thereon equal distances apart and increasing upwardly and inwardly toward the dial shafts.

:Rotatively secured on the shafts Q isa tubular shaft Q which extends through the standards m and m and the rear end of which bears against the .penny indicating wheel (1 Secured on said shaft at the front side of the standard m is a ratchet wheel 0 with its teeth directed oppositely from those of the ratchet. wheel 4, secured on the shaft Q, or in other words secured to rotate the shaft Q," upwardly and inwardly, or on the return movement of the dial C. Pivoted on the standard 111. is a spring'controlled pawl 0 which engages said ratchet wheel and acts to hold the'shaft Q, from rotation when the dial is moving downwardly in counting. Rig idly secured on said shaft Q,- on the rear m is a ratchet wheel 0 having its teeth directed toward the direction of the rotation of the shaft in recording and provided with ten outwardly and radiallydirected teeth 0 corresponding in all respects to the teeth n on the wheel N, be fore described, excepting that said ratchet teeth are free to swing upwardly when engagcd by the teeth o 'of the crown gear 0, but are rigidly locked from downward movement on the ratchet wheel-(1 by means of pins 0 set in the face of said wheel and engaged byla. tail piece 0 on each tooth so thatas the dime dial Creturns to normal, each of the teeth on'said ratchet crown gear successively engage one of the pivoted teeth on said ratche wheel 0 rotating the shaft Q,

to make the count. At the rear end of said shaft and adjacent the penny indicating wheel (f is a dime indicating wheel 9 having marked upon its periphery equal dis tances apart, the ten digits which inasmuch as the shaft Q. rotates oppositely from the shaft Q, are arranged oppositely on said wheel from those on the penny indicating wheel, reading from the top downwardly and outwardly.

Mounted to rotate on the tubular shaft Q, is a tubular shaft Q which projects through the standard m and is provide at its forward end with a ratchet wheel (1 the teeth of which are directed upwardly and inwardly and a spring pressed pawl 51 is pivoted on the standard m and engages said gear to hold the shaft from rotation, when the dial is returning to normal position. A ratchet wheel P is secured on said shaft, at its rear end, and pi oted thereon, as shown in Fig. 17, are ten pivoted outwardly directed teeth 72". Said teeth project radially beyond the periphery of the ratchet wheel P into position to be engaged by the teeth 75 on the crown gear 7), and are free to swing downwardly as said crown gear rotates during the return of the dollar dial B, to normal, but are rigidly held against the upwardly rotation of said gear, as the dial turns downwardly in making the count. In-

asmuch as there are ten of said pivoted teeth on said ratchet wheel, each tooth on the crown gear, rotates the shaft Q one tenth of a revolution in consequence one complete rotation of said shaft indicates ten dollars.

On the inner end of the tubular-shaft Q, is secured a gear 1 which meshes with a gear q? of equal size, as shown in Fig. 6, secured on theshaft of a Veeder register or any other suitable register Q, secured on said base plate M-. Secured also on the Veeder shaft back of the gear q, is a milled wheel a of slightly greater diameter adapted to be manually engaged to-turn the recorder back to 0. The Vceder is slidably secured on said base plate M, by means of a plate 1* which slides on said base plate as shown in Fig. 24, and on which is secured a braclcet r, in which is secured the inner end of a cam shaft R which extends through the base of the V coder and which is provided on its outer end with a milled wheel 1, whereby the same may be rotated. 'Said shaft R, is provided near its inner end wit'ha cam 7*,

f andat its extremity with a collar 9". When the Vceder is pushed inwardly until" the standard 12 engages the block r and the shaft R rotated, the cam 'r rigidly engages behind the-block 1" which is secured to the base-plate M, and thereby rigidly holds the gears q and q in mesh. As shown a spring 1" is secured on the base plate M, and bears against the end of the slide bars r, and acts when the cams are released to throw the 

